Hello,

I have an question regarding my rental contract that I hope you can help me with.

The question is regarding the cancellation of the contract.

It states the following.

Kündigung : Drei Monate im Voraus, Ende März, Ende Juni und Ende September.

As I understand it, it means that I can cancel the contract with the ending date on one of the three mentioned months by informing about it three months before.

Is that corrrectly understood?

Yes. There are "official" moving dates here; those are the ones for your canton. They vary from canton to canton. Contracts are geared around them a lot of the time. That doesn't necessarily mean you can't cancel at other times of the year though. And remember if you do want to cancel your contract you need to send a registered letter to the agency/landlord to arrive before the end of those months; e-mails, phone calls don't count.

"by informing about it three months before."

At least 3 months before, basically the date it arrives counts. To avoid details and loopholes you may decide to add another 10 days and send the registered letter at around the 20th of the month.

The next contractual end date is March 31. For the contrac to end then it's the same whether you send the registered letter now or at the end of December (with the ten additional days I'd send it no later than December 21, just to be on the safe side).